1. Field of the Invention
This invention relates to a surgical apparatus which functions during surgical procedures to reduce blood loss that would otherwise normally occur from cut or similarly exposed blood vessels, especially veins and capillaries by imposing upon these capillaries an amount of air pressure sufficient to interfere with the passage of blood through and out of the damaged blood vessels.
2. Description of the Related Art
Currently there exist several techniques and apparatuses which are used to aid in decreasing blood loss during surgical procedures. Primary of these are the bulky and intrusive direct pressure means which usually consist of the application of direct physical pressure upon a wound by the surgeon's hand, gauze, or bandage. In addition techniques exist which provide for the cauterization and ligation of blood vessels.
One such means for applying direct pressure to a wound is known as a M.A.S.T. suit which is most commonly used as a military anti-shock trouser. This device is essentially an inflatable trouser which is most commonly placed over the lower two-thirds of a person. Once in place, the trouser is inflated to a predetermined pressure thereby preventing further blood loss from the wounded member and squeezing blood from the peripheral to the central blood system. Unlike the present invention, the M.A.S.T. suit does not provide for the additional ability to access the wound site by a surgeon or other medical personnel. Before the wound can be further accessed for proper dressing or additional medical procedures the anti-shock trouser must be deflated and removed, thus allowing the bleeding to begin anew.
Several well-known methods exist for establishing a chamber that increases the barometric pressure within the chamber. Such chambers, most notably the various hyperbaric chambers as disclosed by Gamow et al. in U.S. Pat. Nos. 5,109,837; 5,467,764 and 5,398,678, create a generally short term sealed high pressure environment suitable for an individual to sleep in or to alleviate the conditions associated with high altitude environments commonly known as mountain sickness. In these chambers, the entire patient is inside the chamber and the increased pressure, being system-wide has no effect on bleeding control. U.S. Pat. No. 4,550,713 discloses a system for preventing deformation of an eye when incised that includes a ring sewn to the eye and a means to raise the pressure at the eye to counteract the pressure within the eye.
The present invention overcomes the shortcomings of these prior art methods by providing increased air pressure to be placed on the wound site of the individual contained in an enclosure or around the entire surgical suite, by means of a gas pressure field which limits blood loss. Furthermore, the present invention provides for a means to regulate and provide a variety of gases at various flow rates and mixtures. Also the present invention provides for a means to allow individuals to readily pass into and out of the enclosure.
The art described in this section is not intended to constitute an admission that any patent, publication or other information referred to herein is "prior art" with respect to this invention, unless specifically designated as such. In addition, this section should not be construed to mean that a search has been made or that no other pertinent information as defined in 37 C.F.R. .sctn.1.56(a) exists.